Micrometer



June 4, 1963 H. J. KACHERGIS MICROMETER Filed Feb. 7, 1962 2 Sheets-Sheet 1 INVENTOR Henry J Kachergis MICROMETER Filed Feb. 7, 1962 2 Sheets-Sheet 2 INVENTOR Henry J Kachergis MW TORNEY 3,991,866 Patented June 4, 1963 3,091,866 MICROMETER Henry J. Kachergis, Waterbury, Conm, assignor to Scoviil Manufacturing Company, Waterbury, Conn, a corporation of Connecticut Filed Feb. 7, 1962, Ser. No. 171,685 9 Claims. (will. 33-167) This invention relates to micrometers and particularly to one that has a pretorque factor incorporated in the operating head which makes it especially suitable for measuring the thickness of fabrics or other compressible materials.

When fastener elements are to be attached to a garment, the amount of pressure required to set the fastener element is determined by the thickness of the garment fabric. Due to variations in the amount of force applied to the micrometer head by different individuals, as well as the compressible nature of the fabrics, it has in the past been very diflicult for any two machine operators to arrive at the same micrometer reading on any given fabric. From the various micrometer readings, each operator would es stablish a dilferent setting pressure for his machine with the result that some fasteners would be loosely attached while others would be set too firmly, thereby cutting the fabric around the set fastener and spoiling the garment.

It is the object of this invention to provide a micrometer that embodies within the operating thimble, or in an accessory head, a pretensioned spring that functions to establish a substantially uniform micrometer reading by all operators on any given fabric.

These and other features of the invention will be best understood from the following description of the embodiments thereof as shown in the accompanying drawing, in which:

FIG. 1 is a side view of a standard micrometer with my accessory head applied thereto;

FIG. 2 is a vertical sectional view of the accessory head showing it applied to the head end of a standard micrometer;

FIG. 3 is an exploded perspective view of the several parts employed in the accessory head;

FIG. 4 is a sectional view of a micrometer head showing the pretorque principle embodied directly in the operating thimble of said micrometer;

FIG. 5 is a side view of the gauging end of a micrometer on a piece of fabric and showing the relative position of the anvil and spindle at about the instant the pretensioned head starts to operate; and,

FIG. 6 is a similar view showing the relative position of the anvil and spindle after the pretensionedhead of the micrometer has been operated a prescribed distance.

In the drawing, P16. 1 shows the conventional micrometer consisting of a bow-shaped frame 10, an anvil 11 and an aligned spindle 12 movably mounted in a barrel 13 attached to one ned of the frame 10. The spindle 12 is attached to an operating sleeve or thimble 14 en compassing the barrel 13. The barrel 13 is supplied with the usual indicia 15 graduated to .025 while the thimble 14 is marked with indicia 15 graduated to .001".

The accessory head embodying the feature of my invention consists of a body 17 having a cylindrical portion 18 and a reduced hollow extension 19 providing a shoulder 2t therebetween. The body 17 is secured to the micrometer thimble by a set screw 21 accessible at an exposed part of said body. Another essential part of the accessory head is a pretensioned hollow manipulating sleeve 22 rotatably fitted on the body cylindrical portion 18 and having an inwardly thickened section 23 abutted against the shoulder 20. The outer closed end 24 of the sleeve 22 is also rotatable on a reduced section 25 formed at the end of the body extension 19.

In order to provide a pretensioned force for the operating head, provision is made for a pair of adjustable upper and lower rings 26 and 27. The upper rings 26 will hereinafter be referred to as the spring anchor ring and the lower ring 27 will be referred to as a stop ring. The

lower stop ring 27 rests upon the body shoulder 24) and is releasab-ly secured to the hollow extension 19 by a set screw '28. The ring 27 is formed with a reduced section 29 to provide a pair of opposed shoulders 30 and 30a diametrically opposite each other. The thickened section 23 of the manipulating sleeve 22 carries a set screw 31 having an inward projection 31a that extends into and travels in the clearance 32 provided by the reduced section 29 of the ring 27. Said projection 31a is normally adapted to abut against the right shoulder 39a as viewed in FIG. 3 serving as a stop for the pretensioned sleeve 22 as will appear later.

The preset torque in the accessory head is obtained by means of a coil spring 33 having terminal hooks 33a and 33b. The upper hook 33a engages a pin 34 carried by the closed end 24 of the sleeve 22 and the lower hook 33b engages 2. lug 35 projecting upwardly from the upper anchor ring 26. A sleeve 36 may be disposed between the coil spring 33 and the body extension 19 to prevent said spring from bearing or Wearing against said extension.

All the parts constituting the accessory head are held together as a unit by an assembly washer 37 fitted into a suitable counter-recess 38 in the upper face of the sleeve closed end 24 and held there in place by a screw 40 threaded in the extension 19. The washer 37 is constructed to be non-rotatably mounted on the end of the body extension 19 as by means of lug projections 41 fitted into corresponding slots 42 in said washer.

In order to establish a scale of values to which the pretorque manipulating sleeve 22 may be rotated to meet specified or predetermined adjustments, the outer rim of the body 17 is provided with an index line 43 while the adjacent surface of the sleeve 22 may be provided with an indicia scale 44 of any arbitraly selection that will indicate the amount of rotation of said sleeve to the body 17.

In establishing a pretorque factor in my accessory head, it is first necessary to set up a counter-acting tension be tween the body 17 and the manipulating sleeve 22. This is obtained by winding the spring 33 clockwise. In maloing the necessary adjustments, the accessory head may either be set upon the usual head of a micrometer or some equivalent stem and made secure thereto by the set screw 21. The lower stop ring 27 should first be loosened to rotate freely on the extension 19 which may be accomplished by loosening the screw 23, access to which may be had through an opening 45 in sleeve 22. This allows the sleeve 22 to be rotated relative to the extension 19 beyond the limits of the channel 32 even though the projection 31a of screw 31 may be in contact with the shoulder 34) of the ring 27.

At this point, it should be understood that the spring anchor ring 26 should remain secured to the body extension 19 by means of set screw 46, access to which may be had through an opening 47 in sleeve 22. The set screws used are prefenably the Allen set screws which may be manipulated by a complement-a1 Allen wrench, such as shown at 48 in FIG. 2. Upon loosening the set screw 28, the wrench may be :left in the sleeve opening 45 so that when the sleeve 22 is turned clockwise to wind the spring 33, the stop ring 27 will turn with the sleeve 22. When approximately the right tension is obtained with some amount of lover-winding of the spring to the final tension required, the set screw 28 must be tightened to lock the ring 27 to extension 19. The sleeve 22 will then be reversely turned by the spring 33 until the projection 31a on screw 31 abuts the right shoulder 30a of ring 27 as a stop.

At this point, some minor adjustment may have to be made to align the zero index line on scale 44 with index line 43 on the body 17. This final adjustment may be accomplished by registering the sleeve opening 47 with the anchor ring set screw 46 and inserting the proper wrench and loosening said screw and then with the wrench still in said loosened screw, the sleeve 22, anchor ring 26 and spring 33 may be turned as a unit until the proper alignment is achieved, whereupon the set screws may be tightened.

For all practical purposes in measuring textile materials, it has been established that a pretorque value of about one inch-pound is satisfactory; that is, after the anvil and spindle have confined the material therebetween, the pressure required to rotate the sleeve 22 relative :to the body 17, at the instant that the sleeve 22 begins to rotate relative to the body 17 against the tension force of the spring 33, should be approximately one inchpound. The instant of such turning of the sleeve to the body would position the micrometer spindle 12 [to the anvil 11 with compressed material therebetween at about the position shown in FIG. 5.

In the operation of the accessory head positioned on the micrometer as shown in FIG. 1, the mark on the sleeve indicia scale 44 will normally be registered with the index line 43 on body '17. By turning the head to the leit, the anvil 11 and spindle 1-2 will be separated suificiently to receive the work piece to be gauged therebetween.

In the first stage of the gauging operation, the head will be turned to a position such as diagrammatically shown in FIG. 5 which is the position at the instant that the sleeve 22 begins to turn relative to the body 17 to overcome the pretorque setting of the head. From there on, the sleeve will turn clockwise independently of the body 17, nevertheless, carrying the latter with it at a slower rate of turning while the gauging material is being compressed to some state such as shown in FIG. 6.

The sleeve 22 should then be turned to some designated position as shown on the indicia scale 44, depending on the material being gauged. It will be readily understood that if the same directions are followed by all operators, a uniform gauging of various types of material will result.

In the modified form of FIG. 4, the pretorque principle is embodied directly into the operating thimble of a micrometer. As here shown, the thimble 14a has the usual wedge binding connection with the conical head 12b on the spindle 12a and is formed with an integral reduced extension 1941. A manipulating sleeve 22a is provided that is rotatably mounted on the thirnble 14a similar to that in the first form. The sleeve 22a is rotatably held in place by a washer 37a and screw 46a, the latter also serving to wedgingly bind the thimble 14a to the spindle conical head 12a. In all other respects, the mechanism for winding the spring 33c, holding the sleeve in a pretensioned state and the operation of the micrometer is the same as the first form so further explanation is considered unnecessary.

While two forms of the invention are presented herein for the purpose of exemplification, it will be appreciated that the invention is susceptible of changes and other structurally modified lforms coming equally within the scope of the appended claims.

What I claim is:

l. A micrometer gauge comprising:

(a) la lira-me having an anvil at one end;

(b) a threaded spindle aligned with said anvil;

(c) a barrel extending from the opposite end of said (d) a thimble rotatable on said barrel and connected to said spindle, said thimble having a reduced extension ian-d providing a shoulder therebetween;

(e) a hollow sleeve rotatably mounted on said thimble and providing a space between it and the extension;

(1) a spring anchor ring releasably keyed to said extension;

(g) :a coil spring positioned in said space and having its opposite ends connected respectively to said ring and said hollow sleeve; and,

(11) means for Winding said spring and holding it in a tensioned state thereby imparting a pretensioned torque between said sleeve and said thimble.

2. A micrometer as defined in claim .1 wherein said spring winding and holding means consists of an adjustable ring mounted on said extension between said anchor ring :and said shoulder.

3. A micrometer as defined in claim 2 wherein said adjustable ring has a reduced portion providing opposed shoulders and wherein said sleeve carries an inward projection adapted to abut one of said shoulders as a stop.

4. A micrometer as defined in claim 2 wherein said adjustable ring has a reduced portion providing opposed shoulders and wherein said sleeve carries a set screw having a reduced portion adapted to move in the space provided :by the ring reduced portion and abut one of said shoulders as a stop.

5. A micrometer gauge comprising:

(a) a frame havingan anvil at one end;

(b) a threaded spindle aligned with said anvil;

(c) a barrel extending from the opposite end of said frame;

(d) a thimble rotatable on said barrel and connected to said spindle, said thimble ihaving reduced extension and providing a shoulder therebetween;

(e) a hollow sleeve rotatably mounted on said thi-mble land providing a space between it and the extension;

(1) a coil spring positioned in said space;

(g) means anchoring the opposite ends of said spring respectively to said sleeve and said spindle; and,

(It) means for winding sm'd spring and holding it in a tensioned state thereby imparting a pretensioned torque between said sleeve and said thim-ble.

6. A pretensioned operating head adapted for use with a conventional micrometer including an operating thimble.

(a) said head comprising a hollow body detachably secured to said thimble and provided with a reduced extension to provide a shoulder therebetween;

(b) a hollow sleeve rotatable on said body and providing a space between it and the extension;

(0) a spring anchor ring releasably keyed to said extension;

(d) a coil spring positioned in said space and having its opposite ends connected respectively to said ring and said hollow sleeve; and,

(e) means for winding said spring and holding it in a tensioned state thereby imparting a pretensioned torque between said sleeve and body.

7. A pretensioned operating head as defined in claim 6 wherein said spring-winding and holding means consists of an adjustable ring mounted on said extension between said anchor ring and said shoulder.

8. A pretensioned operating head as defined in claim References Cited in the file of this patent 7 vs herein said adjustable ring has a redu ced portion pr o- UNITED STATES PATENTS vidmg opposed shoulder and wherein said sleeve carries an inward projection adapted to abut one of said shoul- 350,513 Washbum 1886 dens as a stop. 5 1,143,007 Wilcox June 15, 1915 9. A micrometer as defined in claim 7 wherein said 1,444,565 Smith 6; 1923 adjustable ring has a reduced portion and wherein said 2,250,736 f y 29, 1941 sleeve carries a set screw having reduced portion adapted 2,256,473 H1 11 p 23, 1941 to move in the space provided by the ring reduced por- 2,607,219 Mlllafdlet a1 g- 19, 1952 tion and abut one of said shoulders as a stop. 10 2,805,483 Zelnick p 10, 1957 

1. A MICROMETER GAUGE COMPRISING: (A) A FRAME HAVING AN ANVIL AT ONE END; (B) A THREADED SPINDLE ALIGNED WITH SAID ANVIL; (C) A BARREL EXTENDING FROM THE OPPOSITE END OF SAID FRAME; (D) THIMBLE ROTATABLE ON SAID BARREL AND CONNECTED TO SAID SPINDLE, SAID THIMBLE HAVING A REDUCED EXTENSION AND PROVIDING A SHOULDER THEREBETWEEN; (E) A HOLLOW SLEEVE ROTATABLY MOUNTED ON SAID THIMBLE AND PROVIDING A SPACE BETWEEN IT AND THE EXTENSION; (F) A SPRING ANCHOR RING RELEASABLY KEYED TO SAID EXTENSION; (G) COIL SPRING POSITIONED IN SAID SPACE AND HAVING ITS OPPOSITE ENDS CONNECTED RESPECTIVELY TO SAID RING AND SAID HOLLOW SLEEVE; AND, (H) MEANS FOR WINDING SAID SPRING AND HOLDING IT IN A TENSIONED STATE THEREBY IMPARTING A PRETENSIONED TORQUE BETWEEN SAID SLEEVE AND SAID THIMBLE. 